Medication-Assisted Treatment and HIV/AIDS: Aspects in Treating HIV- Infected Drug Users.

Transcription

1 Slide #1 Medication-Assisted Treatment and HIV/AIDS: Aspects in Treating HIV- Infected Drug Users. R. Douglas Bruce, MD, MA, MSc Assistant Professor Yale AIDS Program Medical Director South Central Rehabilitation Center (An Integrated Healthcare Center for Drug Users) Cornell Scott-Hill Health Center

2 NIH Consensus on Drug Treatment Slide #2 Drug addiction is a disorder of the brain and therefore a medical disorder Broader access to drug treatment Reduce federal and state barriers impeding access to treatment Stressed the importance of providing substance abuse counseling, psychosocial therapies, and other supportive services

3 Summary Slide Slide #3 Just as medication can help with depression, medication can help in the treatment of alcohol dependence, opioid dependence, cocaine dependence, nicotine dependence, etc.

4 Slide #4 Neurotoxicity NEUROTOXICITY AIDS, Cancer AIDS Mental illness CANCER MENTAL ILLNESS Homelessness Crime Violence March 10, Health care Productivity Accidents

5 Slide #5 If the societal cost is so high, why do people do drugs?

6 Addiction Slide #6 A state in which an organism engages in compulsive behavior The behavior is reinforcing (that is, pleasurable or rewarding) There is a loss of control in limiting the intake of the substance

7 Slide #7 Why Do People Take Drugs in The First Place? To feel good To have novel: feelings sensations experiences AND to share them To feel better To lessen: anxiety worries fears depression hopelessness

8 Slide #8 Vulnerability Why do some people become addicted while others do not?

9 Slide #9 Biology/genes Biology/ Environment Interactions Environment

10 High DA receptor Low DA receptor DA Receptors and the Response to Methylphenidate (MP) high low Dopamine receptor level Slide #10 As a group, subjects with low receptor levels found MP pleasant while those with high levels found MP unpleasant Adapted from Volkow et al., Am. J. Psychiatry, 1999.

11 DA D2 Receptor Availability Control Addicted Slide #11 Dopamine D2 Receptors are Lower in Addiction Cocaine DA DA DA DA DA DA DA DA DA DA DA DA Meth Reward Circuits Non-Drug Abuser Alcohol DA DA DA DA DA DA Heroin March 10, Reward Circuits Drug Abuser

12 Slide #12 Drugs Are Usurping Brain Circuits and Motivational Priorities

13 Slide #13 This is why addicts can t just quit This is why treatment is essential

14 Slide #14 Treatment for Addiction Includes: 1. Pharmacological (medications) 2. Behavioral Therapies 3. Medical treatment for the complications of addiction (e.g., HIV, HCV therapy) 4. Social Services

15 Slide #15 Pharmacology in Primary Care: Opioids = Buprenorphine

16 Heroin Slide #16 Heroin is a short-acting, semisynthetic opioid produced from opium that can be smoked, sniffed, or injected. Heroin euphoria begins shortly after injection and lasts ~ 1 hour, followed by 1-4 hours of sedation; withdrawal symptoms or craving begin several hours later. Most heroin dependent individuals inject 2-4 times per day. Many mediate sedating effects by injecting a small amount of cocaine, if available (not in Russia or Asia), known as a "speedball." Sometimes crack is smoked as a substitute. Unsterile use, unpredictable concentrations in street samples, adulterants in injection mixture, lifestyle necessary to procure drugs are responsible for most heroin-associated medical complications.

17 Effects of Buprenorphine Dose on µ-opioid Receptor Availability in a Representative Subject Slide #17 Binding Potential (Bmax/Kd) MRI 4 - Bup 00 mg Bup 02 mg 0 - Bup 16 mg Bup 32 mg Slide Courtesy of Laura McNicholas, MD, PhD

18 Medication Assisted Treatment - Opioids Slide #18 Rationale Cross-tolerance prevent withdrawal relieve craving for opioids Narcotic blockade block or attenuate euphoric effect of exogenous opioids Pharmacotherapy Buprenorphine Methadone LAAM Naltrexone

19 Intrinsic Activity Slide # Intrinsic Activity Log Dose of Opioid Full Agonist (Methadone) Partial Agonist (Buprenorphine) Antagonist (Naltrexone)

20 Buprenorphine, Methadone, LAAM: Treatment Retention Slide # Percent Retained % Hi Meth 58% Bup 53% LAAM 20% Lo Meth Study Week

21 Buprenorphine, Methadone, LAAM: Opioid Urine Results Slide #21 Mean % Negative All Subjects 49% 40% 39% 19% LAAM Bup Hi Meth Lo Meth Study Week

22 Buprenorphine Slide #22 Every physician treating HIV-infected drug users should have an X waiver and be ready to prescribe. The 1, 2, 3 of BUP: 1. It is easier than HIV/HCV treatment. 2. It is safer than prescribing oxycodone for pain or alprazolam for anxiety. 3. It is desperately needed to expand access to treatment.

23 Slide #23 Pharmacology in Primary Care: Cocaine = Disulfiram

24 Cocaine Slide #24 Cocaine hydrochloride is a water-soluble salt which is injected or taken by nasal inhalation, snorted. Although cocaine hydrochloride is destroyed by heat, it may be chemically converted to a free-base ("crack") cocaine, which can be smoked. Pulmonary absorption of crack is as rapid as IV injection. Cocaine s half-life is short, resulting in the need for frequent administration; active cocaine users may inject or inhale cocaine as many as 20 times a day. Cocaine induces feelings of elation, omnipotence and invincibility and with volatile behavior and rapid development of dependence. Cocaine use is associated with high risk sexual behavior.

25 Site of Cocaine Binding Slide #25

26 Disulfiram Slide #26 Increases dopamine in the brain by inhibiting dopamine beta hydroxylase. 6 RCTs have demonstrated efficacy in treating cocaine dependence. Dosage: 250 mg/day No studies in HIV/HCV populations so need to watch AST/ALT Problem remains adherence. Works well with the motivated patient or the patient who is administered it with methadone.

27 Slide #27 Pharmacology in Primary Care: Methamphetamine = Buproprion

28 Methamphetamine (MA) MA is a psychostimulant similar in chemical structure to amphetamine with more profound effects on the CNS and can be smoked, snorted, injected, or administered rectally. Produces stimulation and feelings of euphoria and has a long duration of action (6 to 8 hours after a single dose) Tolerance develops rapidly and escalation of dose and frequency is required. As with cocaine, MA use is associated with high risk sexual behavior (especially in MSM) Neurocognitive effects of MA use worse in HIV positive patients.. Slide #28

29 Slide #29 Dopamine Transporters in Methamphetamine Abusers Dopamine Transporter Bmax/Kd Time Gait (seconds) Motor Task Loss of dopamine transporters in the meth abusers may result in slowing of motor reactions. Memory task Loss of dopamine transporters in the meth abusers may result in memory impairment. 6 Delayed Recall (words remembered) Volkow et al., Am. J. Psychiatry, Normal Control Methamphetamine Abuser

30 Treatments Slide #30 Bupropion 150 mg twice daily has shown some reduction in use among mild methamphetamine users (Shoptaw, DAD. 2008) Counseling remains the mainstay

31 Slide #31 Pharmacology in Primary Care: Alcohol = Naltrexone

32 Alcohol Main Points Slide #32 Disinhibition that leads to increased risktaking behaviors and poor adherence to all treatments Withdrawal seizures The drug that really is frightening because it is neurotoxic and accelerates HCV disease progression CAGE Questions

33 ETOH Treatment Slide #33 Naltrexone FDA approved and standard of care Watch for hepatotoxicity (black box warning) Dosages: 100 mg per day (based on COMBINE study) Acamprosate FDA approved, but inferior to naltrexone Disulfiram FDA approved, but inferior to naltrexone

34 Topiramate Slide #34 Not FDA approved for ETOH dependence 8 papers showing efficacy of topiramate for ETOH dependence Doses varied by trial, but typically patients were started low (25 mg daily) and titrated up to a max of 300 mg over 6 weeks. Important choice because: 1.Can give to patients on opioids 2.Moderates symptoms of withdrawal

35 Slide #35 Pharmacology in Primary Care: Nicotine = Nicotine

36 The 5 A s Slide #36 Ask about tobacco use Advise smokers to quit Assess willingness to quit Assist with quitting Arrange follow-up Brief advice to quit does make a difference!

37 Pharmacotherapy Slide #37 Nicotine replacement helps Buproprion doubles quit rates (but is metabolized by CYP 2B6 so possible interactions with NFV, RTV, and EFV). Doses 150 mg to 300 mg effective. Varenicline better than buproprion and nicotine in comparison trials watch for suicidality and exacerbation of neuropsychiatric symptoms. Slow upward titration to minimize side effects.

38 Slide #38 Continuum of Interventions Knowing the Pieces

39 Range of Treatments Slide #39 Risk (Harm) Reduction Decrease frequency of adverse events related to a behavior Change in use behavior e.g., Changing from injection use to sniffing Risk (Harm) Removal Cessation of substance abuse Abstinence based 12 Steps Agonist based buprenorphine, methadone

40 Slide #40 Harm reduction is critical because drug addiction is a chronic illness with relapse rates similar to those of hypertension, diabetes, and asthma McLellan et al., JAMA, 2000.

41 Relapse Rates Are Similar for Drug Addiction & Other Chronic Illnesses Drug Addiction Type I Diabetes Hypertension Asthma Slide #41 Percent of Patients Who Relapse 40 to 60% 40 to 60% 30 to 50% 30 to 50% 50 to 70% 50 to 70% 50 to 70% 50 to 70% McLellan et al., JAMA, 2000.

42 Slide #42 There is a right way and a wrong way to Measure the Outcome of Treating Chronic Illnesses like Addiction Hypertension Tx YES Addiction Tx NO Stage of Tx Stage of Tx

43 DAT Recovery with prolonged abstinence from methamphetamine [C-11]d-threo-methylphenidate Normal Control high Slide #43 There is hope!! Methamphetamine Abuser (1 month detoxification) low Methamphetamine Abuser (14 month abstinent) Volkow et al., J. Neuroscience, 2001.

44 Slide #44 Questions?